Improvement in steam-generatoks



@uitrit tutte getraut @frn S. LLOYD WIEGAND, OF PHILADELPHIA, PENNSYLVANIA.

` Letters Patent No. 67,621, darai August 6, 1867.

IMPROVEMENT IN STEAM-GENERATORS.

'ro ALL WHoM IT MAY ooNoEnN: v

Beit known that I, S. LLOYD WIEGAND, ofthe city of Philadelphia, and State ofPennsylvania, have invente a new and useful Steam-Geueratorg and I do hereby declare that the following is a full, clear, and exact ldescription thereof, reference being had to the accompanying drawings, and the letters of reference marked thereon.

Figure 1 is a sectional elevation thereof.

Figure 2 is a front elevation thereof, and

Figure 3 is a plan thereof. Y

The same letters of reference apply to the same parts in the several iigures.

The nature of this invention consists in forming a steam-generator of aseries of vessels connected together, and havingtubes descending therefrom into a fire-chamber, and providing each tube with an arrangement which insures an active circulation of water in it, and at the same time avoiding suchjoints as are diiicult to make or repair by ordinary laborers. By this means I am enabled to make a boiler which can be readily put together or transported in parts or sections and erected without dithculty, and at the same time a boiler that is compact, and therefore requiring an inexpensive setting, and which, by reason of containing at any time but a small volume of water, is not liable to destructive explosion.

I will now proceed todescribe more particularly the construction and operation oi' this invention.

In a furnace-chamber, A, is placed a number of vertical or inclined tubes, B, which are closed at the lower end, and at the upper end are inserted Ainto rectangular iron vessels, with which they have free communication. Within the tubes B are placed other smaller tubes, D, which extend from near the bottom of the external tube to a short space above the bottom of the vessels C, and pass through a perforated plate, E, placed parallel with the bottom of the vessel C. The vessels C are connected with a steam-drum or main steam pipe, F, by means of the pipes G, and are supplied with water and emptied by means of the pipes I'I connecting them with the pipe I, on which are placed the feed-cock or valve K and the blow-ofi' cock or valve L.

Upon water being supplied to the boiler to about the level of the perforated plates E, and heat being applied in the furnace, an ascending current is formed in the annular spaces between the tubes D and B, and a descending current in the tube D, and this circulating action becomes more and more active, as the temperature is increased, by reason of the heated column `of Water containing bubbles of steam between the tubes B and D being lighter than the column of less heated water in the tubes D. The functions of the perforated plate E are to support the tubes D, and also to facilitate the separation oi`the steam from the currents of water rising from the annular spaces between the tubes B and D.

The tubes D are kept in position at the lower ends by means of projections, N, cast in the caps M, which close the lower ends of the tubes B. These caps, M, are screwed upon the tubes B, and the tubes are attached to the vessel C by being screwed into the bottomtliereof. The ends of the vessels C are made with apertures closed with thegplatesO secured by bolts Band bridge-bars Q and nuts R, and afford facilities for the introduction of the perforated plates E and the removal of the core used in` casting them,and also for inspection and/'cleansing, when necessary, The internal tubes may be made of different material from the external tubes, and a galvanic action thus produced so as to promote the durability and cleanliness of the boiler.

A steam-generator thus constructed possesses the following advantages, not common to others: Itis more cheaply constructed than others. All of the parts are of such form and dimensions as not to require any great thickness of metal to impart thestrength requisite for safe use. None of the parts are of such size or form as to be inconvenient for transportation. It requires but little skill to erect the boiler. All'of the tubes are free to expand and contract, independently of each other, ,and thus avoid straining and liability to leakage. There is never at one time a large volumel of water contained in the boiler, so that in the event of a rupture of any portion of the boiler a destructive explosion cannot ensue. Any of the tubes may be removed without disturbing the others. The circulation of the water in the boiler when in use is so active as to preclude the deposit of sediment in the tubes, and the heating surface is thus preserved in a condition of the greatest eiciency. The boiler can be enlarged by the addition of other vessels, with the tubes connected therewith, without incurring expensive alterations of the portions already erected.

WhatrI claim as my invention, anddesire' to secure as such by Letters Patent, are-'- 1. The combination of the externnl'and internl tubes, as described, with the vessels into which they are inserted, and the perfiatefl plate or plates, as described. I

2. The construct/ion of screw-cps M, as shown and described.

3. The making of the internal and external cubes of different metals, so as to produce a galvanic action lthereby.

S. LLOYD WIEGAND.

Witnesses:

SAMUEL LOAG, WM. H. LOAG. 

